Brake



R. 1:. ST. JAMES Sept. 6, 1932.

BRAKE Filed Oct. 30. 1930 INVENTOR ma l 7. (Si china BY,

Patented Sept. 6, 1932 I UNITED STATES PATENT OFFICE ROBERT '1". ST.JAMES, OF CHICAGO, ILLINOIS, ASSIGNOR T0 BENDIX BRAKE COMPANY,

OF SOUTH BEND, INDIANA, A CORPORATION OF ILLINOIS Application filedOctober 80, 1980. Serial No. 492,277.

in a rounded notch forming one angle of an opening in one of the shoeends, the opening preferably being generally triangular in outline sothat it affords clearance for the movement of the cam in applying andreleasing the brake. Preferably, the two ends of the friction means arearranged side by side and there is a generally triangular opening ineach of the ends, with the apex of each opening opposite the base of theother so that a cam projecting through the openings may have itsoppositely directed ends or lobes fitting into and operatively journaledin the rounded seats formed at the apexes of these triangular openings.Thus the cam moves the shoes or their e uivalents positively in bothdirections in app ying and releasing the brake so that there is nopossibility of a shoe dragging when the brake is released.

The above and other objects and features of the invention, includingvarious novel and desirable details of constructiomwill be apparent fromthe following description of the illustrative embodiment shown in theaccompanying drawing, in which:

Figure 1 is a vertical section through the brake just inside the head ofthe brake drum and showing the brake shoes in side elevation;

Figure 2 is a partial section on the line 22 of Figure 1 and showing themounting of the cam; and

Figure 3 is a partial section on the line 33 of Figure 2, but on alarger scale and showing a modified shape of opening in the ends of theshoes.

The illustrated brake includes a rotatable drum 10, at the open side ofwhich 1s a suit able support such as a backing plate 12 and within whichis arranged the friction means of the brake. The illustrated frictionmeans includes a pair of shoes 14 notched at their I lower ends toembrace a fixed anchor 16 carried by the backing plate 12 and againstwhich the shoe ends are held by a spring 18 tensioned between the shoes.v

According to the present invention, the upper ends of the webs of theshoes are oil'- set sufiiciently so that they extend past each other andare arranged side by side. These ends are formed with openings 20,generally triangular in outline, through which there extends anoperating cam 22 shown as mounted on a cam shaft 24 journaled in thebearing 26 carried by the backing plate12.

In the arrangement of Figure 1, the upper apex of the opening 20 in therighthand shoe 14 and the lower apex of the opening 20 in the lefthandshoe 14 are formed as rounded seats into which there fit the roundedopposite lobes of the cam 22. When the brake is released, in thisparticular arrangement, the side of the cam is engaged by one side ofeach of the openings 20. It will be seen that the lobes of the cam 22not only apply the shoes positively when it forces them the shoe ends.In this case the openings 120' are generally in the form of equilateraltriangles so that the side of the opening does not engage the cam whenthe brake is released and the position of the shoe is determinedentirely by the rounded notch or seat at the apex of its opening 120which is journaled on the upper or lower end of the cam 122.

While two illustrative embodiments of the. invention have been describedin detail, it is not my intention to limit its scope to those particularembodiments or otherwise than by the terms of the appended claims.

I claim 1. A brake comprising friction means having adjacent relativelymovable ends 'ar-- ranged side by side and an o erating cam acting onsaid ends, said ends ing formed with openings embracing said camso thatthe cam moves the ends. positively in both directions.

2. A brake friction device havin in its m end an opening generallytriangular in form with its apex formed as a rounded seat, incombination with a cam projecting into said 0 ning and havingan'operating portion fitting into and journaled in said seat. 1 3. Abrake comprising friction means havin its ends arranged side by side,said ends being formed with openings of oppositely dis- I posed nerallytriangular outlines, the apex of eac of said triangles being oppositethe a base of the other and eing rounded to form a seat, in combinationwith a cam projecting into said openings and having operating'portionson o posite sides of its axis and which fit into an are journaled insaid seats '33 respectively.

In testimony whereof, I have hereunto signed my name.

, ROBERT T. ST. JAMES.

